Postgres: ERROR: type "string" does not exist

[shietpas]

Describe the bug
I have a pre-aggregate defined as an External Rollup, where Postgres is the database type for pre-aggregations. When cube.js attempts to create the pre-aggregate table, it defines some fields as data type "String", which is not supported in Postgres. Similar to following
CREATE TABLE stb_pre_aggregations.my_dimension_and_date_pavk001m_lhrjued2_1564600063903 ("myCol1" STRING, "myCol2" STRING, "myMeasure" FLOAT)"

Exception: textPayload: "{"message":"Error querying db","query":"SELECT xxxx","params":["2019-01-01T00:00:00Z","2019-12-31T23:59:59Z"],"error":"Error: type "string" does not exist\n at QueryQueue.parseResult (/srv/node_modules/@cubejs-backend/query-orchestrator/orchestrator/QueryQueue.js:75:13)\n at QueryQueue.executeInQueue (/srv/node_modules/@cubejs-backend/query-orchestrator/orchestrator/QueryQueue.js:64:19)\n at \n at process._tickDomainCallback (internal/process/next_tick.js:229:7)"}"
timestamp: "2019-07-31T19:08:12.527Z"

To Reproduce
Steps to reproduce the behavior:

1. Define cube schema using Big Query as primary database type
2. Define pre-aggregate with "external: true" for External Rollup
3. Define external database type to be Postgres
4. Run query that would result in pre-aggregate creation

Expected behavior
Table should be created in Postgres under stb_pre_aggregations schema that reflects pre-aggregation table using valid Postgres data types.

Screenshots
If applicable, add screenshots to help explain your problem.

Version:
0.10.16

Additional context
Using serverless-google-cloudfunctions

[paveltiunov]

@shietpas Thanks for posting this!

Need to implement this one: https://github.com/cube-js/cube.js/blob/353ed631bd9c227f4d9d77df63b2ebf900a680ed/packages/cubejs-query-orchestrator/driver/BaseDriver.js#L157

[shietpas]

@paveltiunov I assume this means overriding the fromGenericType method in the PostgresDriver.js file. Can I edit that in this GitHub project (fork/PR)? I'm not familiar with how that ends up in npm under @cubejs-backend/postgres-driver package.

[paveltiunov]

@shietpas Yep. You can fork and then provide PR. We'll release it for npm then.